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Exchangeable Securities (Details) - CAD ($) $ / shares in Units, $ in Millions |  |  |  |  | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Oct. 30, 2020 | May 25, 2019 | May 22, 2019 | May 01, 2019 | Dec. 31, 2020 | Dec. 31, 2018 | Oct. 22, 2020 | Dec. 31, 2019 | Jul. 20, 2018
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |  |  |
Minimum proceeds for each redemption of exchangeable securities |  |  |  |  |  | $ 100 |  |  |
Interest rate |  |  |  |  |  |  | 4.07% |  | 4.509%
Investment Agreement | Discount rates |  |  |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |  |  |
Percentage of reasonably possible increase in unobservable input, liabilities |  |  |  |  | 1.00% |  |  |  |
Investment Agreement | Brookfield Renewable Partners |  |  |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |  |  |
Proceeds on sale of an organizational unit |  | $ 750 | $ 750 |  |  |  |  |  |
Other cash receipts from sales of equity or debt instruments of other entities, classified as investing activities | $ 400 |  |  | $ 350 |  |  |  |  |
Investment Agreement | Brookfield Renewable Partners | Minimum ownership interest threshold to increase ownership interest to 49% |  |  |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |  |  |
Proportion of ownership interests held by non-controlling interests |  |  |  |  | 8.50% |  |  |  |
Investment Agreement | Brookfield Renewable Partners | Hydro | Ownership interest, less than, threshold which triggers one time option to increase ownership interest |  |  |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |  |  |
Equity participation percentage |  |  |  |  | 49.00% |  |  |  |
Investment Agreement | Brookfield Renewable Partners | Hydro | Top up option for ownership interest percentage, 20 day VWAP is not less than $14 per share |  |  |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |  |  |
Additional proportion of ownership interests held by non-controlling interests allowed to be acquired |  |  |  |  | 10.00% |  |  |  |
Investment Agreement | Brookfield Renewable Partners | Hydro | Top Up Option For Ownership Interest Percentage, 20 day VWAP is not less than $17 per share |  |  |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |  |  |
Equity participation percentage |  |  |  |  | 49.00% |  |  |  |
Investment Agreement | Brookfield Renewable Partners | Hydro | Ownership interest threshold if exceeded requires redemption price in cash |  |  |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |  |  |
Equity participation percentage |  |  |  |  | 49.00% |  |  |  |
Investment Agreement | Brookfield Renewable Partners | Hydro | Minimum | Top up option for ownership interest percentage, 20 day VWAP is not less than $14 per share |  |  |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |  |  |
Weighted average share price |  |  |  |  | $ 14 |  |  |  |
Investment Agreement | Brookfield Renewable Partners | Hydro | Maximum |  |  |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |  |  |
Equity participation percentage |  |  |  |  | 49.00% |  |  |  |
Investment Agreement | Brookfield Renewable Partners | Hydro | Maximum | Top Up Option For Ownership Interest Percentage, 20 day VWAP is not less than $17 per share |  |  |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |  |  |
Weighted average share price |  |  |  |  | $ 17 |  |  |  |
7% Unsecured Subordinated Debentures Due May 1, 2039 |  |  |  |  |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |  |  |  |  |
Interest rate |  |  |  | 7.00% | 7.00% |  |  | 7.00% |

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